Some HTTP/2 implementations are vulnerable to window size manipulation and stream prioritization manipulation, potentially leading to a denial of service. The attacker requests a large amount of data from a specified resource over multiple streams. They manipulate window size and stream priority to force the server to queue the data in 1-byte chunks. Depending on how efficiently this data is queued, this can consume excess CPU, memory, or both.
Published: 2019-08-14
A variety of Denial of Service vulnerabilities were found in third-party implementations of HTTP/2.
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https://www.oracle.com/technetwork/security-advisory/cpuoct2019-5072832.html
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https://www.debian.org/security/2020/dsa-4669
https://www.debian.org/security/2019/dsa-4511
https://www.debian.org/security/2019/dsa-4505
https://usn.ubuntu.com/4099-1/
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https://support.f5.com/csp/article/K02591030
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https://security.netapp.com/advisory/ntap-20190823-0002/
https://seclists.org/bugtraq/2019/Sep/1
https://seclists.org/bugtraq/2019/Aug/40
https://kc.mcafee.com/corporate/index?page=content&id=SB10296
https://kb.cert.org/vuls/id/605641/
https://github.com/Netflix/security-bulletins/blob/master/advisories/third-party/2019-002.md
https://access.redhat.com/errata/RHSA-2019:4021
https://access.redhat.com/errata/RHSA-2019:4020
https://access.redhat.com/errata/RHSA-2019:4019
https://access.redhat.com/errata/RHSA-2019:4018
https://access.redhat.com/errata/RHSA-2019:3935
https://access.redhat.com/errata/RHSA-2019:3933
https://access.redhat.com/errata/RHSA-2019:3932
https://access.redhat.com/errata/RHSA-2019:3041
https://access.redhat.com/errata/RHSA-2019:2966
https://access.redhat.com/errata/RHSA-2019:2955
https://access.redhat.com/errata/RHSA-2019:2949
https://access.redhat.com/errata/RHSA-2019:2939
https://access.redhat.com/errata/RHSA-2019:2925
https://access.redhat.com/errata/RHSA-2019:2799
https://access.redhat.com/errata/RHSA-2019:2775
https://access.redhat.com/errata/RHSA-2019:2746
https://access.redhat.com/errata/RHSA-2019:2745
https://access.redhat.com/errata/RHSA-2019:2692
http://lists.opensuse.org/opensuse-security-announce/2019-10/msg00014.html
http://lists.opensuse.org/opensuse-security-announce/2019-10/msg00005.html
http://lists.opensuse.org/opensuse-security-announce/2019-10/msg00003.html
http://lists.opensuse.org/opensuse-security-announce/2019-09/msg00035.html
http://lists.opensuse.org/opensuse-security-announce/2019-09/msg00032.html
http://lists.opensuse.org/opensuse-security-announce/2019-09/msg00031.html